北海道天塩川水系一支流におけるイトウ成魚の夏季生息場所利用 : イトウ生息地保全事項の提示

概要

論文の詳細を見る
The summer habitat of adult Sakhalin taimen (Hucho perryi) was studied in a fourth-order tributary of the Teshio River, Hokkaido. Sakhalin taimen selected large pools with slow water velocity and canopy shade or cover (especially canopy shade). The maximum number of Sakhalin taimen observed in pools during three censuses was positively correlated with the percentage of canopy shade or cover, while the maximum body size was positively correlated with the bed area. The study section had a reach within some nature-oriented river works, but no taimen were found there, probably because of insufficient pool sizes and canopy shade or cover patch for this species. On the other hand, Sakhalin taimen in this study stream are known to spawn from May to June in first-, second- and third-order streams where meandering channels and riparian forests are well preserved. These results suggest the importance of preserving large deep pools with canopy shade or cover and allowing adult taimen to migrate upstream (first-, second- and third-order streams) and downstream (fourth-order streams) throughout the river system.
日本生態学会の論文
2002-08-10